Sizing agent for textile fibers derived from methanolysis of a vinyl acetate acrylamide copolymer



Unitcd States Patent Office SIZING AGENT FOR TEXTILE FIBERS DERIVED FROMMETHANOLYSIS OF A VINYL ACETATE ACRYLAMIDE COPOLYMER Shiro Masuda, KozoKonishi, Masaaki Suzui, and Tetsuyuki Sakamoto, Ohmi-machi, NishiKubiki-gun, Japan, assignors to Denki Kagaku Kogyo Kabushiki Kaisha,Chiyoda-ku, Tokyo, Japan No Drawing. Filed Nov. 3, 1967, Ser. No.680,360

Int. Cl. Cm 7/26; C08f /20 US. Cl. 260--85.7 6 Claims ABSTRACT OF THEDISCLOSURE A warp sizing agent is prepared by the partial saponificationof a vinyl acetate-acrylic amide copolymer. This product is superior toa mixed size including acrylic acid ester and polyvinyl alcohol in termsof such adhesiveness, softness and moisture absorptive property whichcan be adjusted to suit the particular fibers to be sized by the degreeof saponification. In addition, the product is characterized by case ofhandling, transporting and weighing because of its powdery state, and isreadily dissolved in water.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to a sizing agent for textile fibers, of all types butespecially hydrophobic ones such as polyester and polyamide warp yarnsof which are usually sized before weaving.

Description of the prior art SUMMARY OF THE INVENTION The object of thisinvention is to provide a warp size which is also satisfactory forhydrophobic fiber such as polyester and polyamide, wherein the sizing ofwhich is usually effected by the combined use of partially saponifiedpolyvinyl alcohol and acrylic acid ester size, with the consequentproblem of large moisture absorptive property, which causes diflicultyin the weaving.

This warp size can be used alone, without another chemical, unlike theconventional size. Having better cohesive force also contributes to theimproved quality of the product woven fabrics.

Moreover, the size of this invention is obtained in powdery form withhigher purity, is readily transported, weighed and handled and is easilydissolved in water.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Generally, in the weavingoperation, the warp yarn is first reinforced and lubricated by treatmentwith an appropriate agent called a szie, and such warpsize need beselected according to the kind of the wary yarn to be sized.

For example, in the case of hydrophobic fibers such as polyester orpolyamine, satisfactory sizing cannot be effected using a partiallysaponified polyvinyl alcohol 3,525,723 Patented Aug. 25, 1970 alone, anacrylic acid ester size has greater adhesiveness in comparison withpolyvinyl alcohol, but suffers the defect in having a substantialmoisture absorptive property. In practice, a mixed size containingsaponified polyvinyl alcohol and acrylic acid ester is used.

In our researches on szies for Warp yarn, we have found that the sizingagent for textile fibers of this invention can be independently used notonly for the hydrophilic fibers but also for said hydrophobic fibers,because its excellent adhesiveness, softness and moisture absorptiveproperty can be adjusted to best suit the kind of fiber to be sized.

Besides, in comparison with the combined use of polyvinyl alcohol andacrylic sizes, which are now popular, the size of this invention hadbetter cohesvie force, and consequently with the use of this size, theweaving process can be smoothly performed. Our tests also indicate thatthe quality of woven fabrics is improved where the warp yarns have beenprocessed by this size.

The size of this invention is readily soluble in water without theaddition of another chemical.

The size of this invention can be obtained by copolymerizing vinylacetate and acrylic amide, and then partially saponifying the saidcopolymer.

It is especially important for the product to have an appropriateacrylic amide content and saponification degree, so that the size willhave the desired adhesiveness, elasticity, moisture absorptive property,and superior cohesive force in powdery state.

That is, as the acrylic amide content in the acrylic amide copolymerpartially saponified part becomes greater, the moisture absorptiveproperty becomes larger, and the sized warp yarns contain too muchmoisture accordingly. This of course, is undesirable in the weavingprocess, as tackiness of the yarn increases. On the other hand, as theacrylic amide content becomes smaller, the sizing process becomes moredifiicult to perform, and simultaneously, the abrasion resistance andsoftness of the processed warp yarns are reduced.

An appropriate acrylic amide content in the saponified copolymer is02-17 mol. percent, and by converting about -95 mol. percent of residualacetic acid radical contained in the partially saponified copolymer tothe hydroxylic group, the size can be obtained in powder state withease.

If the conversion is less than 75 mol. percent obtaining the size inpowder state becomes increasingly difficult.

When the residual acetic acid radical converted to hydroxyl radicalexceeds mol. percent, then desizing becomes almost impossible to effect.

In the copolymerization of vinyl acetate (M and acrylic amide (M themonomer reactivity ratio is r 0.07, r 7.5 respectively and therefore inorder to obtain uniform copolymer it is better to copolymerize in unisonwith each other by adding the acrylic amide (having faster reactionvelocity) gradually, in proportion to the polymerizing degree of vinylacetate (having slow reaction velocity).

The invention is hereinafter explained in detail, referring to thefollowing examples. However, it should be understood that these examplesare not intended to restrict this invention but are given merely by wayof illustration. In the examples, the terms part or percent mean byweight, unless otherwise specified.

EXAMPLE 1 By adding continuously a total of 0.10 part of acrylic amideto copolymerized liquid composed of 0.0053 part ofazobisisobutyronitrile as against 1 part of vinyl-acetate, and 1.13parts of methanol, polymerization proceeds for about 12 hours at atemperature of 65 C. and vinyl acetate and acrylic amide copolymer inthe yield of more than 99% is produced.

In the next step, to a solution composed of 30 parts of the saidcopolymer and 70 parts of methanol, mole of sodium methylate per onemole of vinyl acetate is added and the saponifying reaction is performedat a temperature of 40 C. The product is a partially saponified vinylacetate and acrylic amide copolymer having polymerization degree 500with 85 mol. percent saponification degree of acetic acid radicals (theproduct is Item No. l of this invention as indicated in Table 1).

Other copolymers are prepared and then saponified as previouslydescribed but starting with 0.024 and 0.002 parts of acrylic amideinstead of 0.10 part. These products are designated Item 2 and Item 3,respectively in Table 1.

After dissolving these three products, polyester warp yarns were sizedwith them having use of a two-step roller type sizing machine and thefundamental property as of each of the thus sized Warp yarns weredetermined.

The sizing conditions and the test results are shown in Table 1. Also,for purpose of comparison the same data were determined for the samekind of yarns sized in the same way but using 4.2 parts of partiallysaponified (saponification degree 88 mol. percent) polyvinyl alcoholalone, (designated in Table I as comparative size No. 1), and thecombined use of 4.2 parts as above-stated, of this partially saponifiedpolyvinyl alcohol, and 1.8 parts Marposol S-50 (trademark: Acrylic warpsize, manufactured by Matsumoto Oil and Fat Co., Ltd.) (designated inTable 1 as size No. 2).

As indicated in Table 1, Item No. 2 of this invention is superior interms of pliability and cohesive force, to comparative size No. 2.

Even though the size takeup is less than that of comparative size No. 2,Item No. 2 of this invention size results in a higher value for thecohesive force.

Besides, it is recognized that relating to moisture absorptive propertyin the case of Item No. l of this invention size, it is limited by theextent of increase in acryl c amide content, while in the case of ItemNo. 3 of this invention size, its friction resistance is limited also bythe extent of decrease in acrylic amide content.

TABLE 1 Com- Comparapara- Item of this invention tive tive size size No.1 No. 2 No.3 No. 1 No.2

Acrylic amide content (mol percent).. 11 2 0.3 "5 7 Siz?1 takeup(percent). 5. 5 5. 1 5. 0 4. 9

sive force zti ines) 32 28 23 19 Pliability 108 138 165 180 175 Warpfilament, polyester 50 d., 24 F. twist 300 times/m. Property test(temperature and humidity C. RH

The composition of sizing bath: Percent Items of the invention orcomparative sizes 6 Saitex T-190 1 0.4 Scourol 100 2 0.5

Saitex T-190, manufactured by Geo Chemical Co. Flux. Scourol 100,manufactured by Kao Soap 00., Flux.

Cohesive f0rce.-Tested by use of Friction & Rubbing tester, TM-type.After setting sized yarns at a bending angle of by use of three piecesof steel pin, one end of the yarns is fixed, with the other end burdenedwith tension of 10 g./one piece.

On exerting friction on the sized yarns by moving three pins in parallelwith the filaments, the times needed for moving the pins until thefilaments are separated were measured.

Pliability.--Tested by stiffness tester, twisting type. One end of sizedfilament (3 cm.) in length fixed to a movable pulley, while attaching amagnetic substance to the other end in such manner of the substance mayhang down vertically and settle in a less powerful magnetic field.

When the movable pulley rotates at a velocity of 1 r.p.m., if therotation angle of the pulley needed until a magnetic substance revolvesat a certain angle (go) is set at 0, pliability is given as follows.

Pliability: g0/9 X 100 The lower this value the greater is the softnessof the material.

Acrylic amide content-computed out by nitrogen analysis. As indicated inTable 1, Item No. 2 of this invention is superior in terms of pliabilityto comparative size No. 2.

Even when the size takeup is lower than that of comparative size No. 2,Item No. 2 of this invention still shows a higher value for the cohesiveforce.

Besides, it is recognized that relating to moisture absorptive propertyof Item No. 1 of this invention, it is limited by the extent of increasein acrylic amide content, while in the case of Item No. 3 of thisinvention, its elasticity is limited also by the extent of decrease inacrylic amide content.

EXAMPLE 2 Comparison was made between the following cases. That is, thecase of employing Item No. 2 of this invention as warp size as indicatedin Example 1, and the case of partially saponified polyvinyl alcohol andacrylic acid ester size as now used commonly (comparative size No. 2 asindicated in Table 1).

By using a total of 4600 sized warp yarns on automatic loom, on theright side of which invention Item No. 2 sized warps numbering 2300 wereset, and 2300 comparative goods No. 2 sized warp on the left siderespectively, the weaving test was conducted.

The result is that the warp sized with the invention size which were cutduring the weaving averaged one per 36 yards of cloth while, on the sidehaving the warp yarns sized within the comparative size the yarn was cutat the rate of one yarn per 7.7 yards woven fabric. That is, therat1io5of cut yarns during weaving between the two sizes 1s The sizingconditions were as shown in Example 1, while the weaving conditions wereas follows:

Temperature and humidity during the weaving--24-28 C., 74-82% RH.

Loom rotation timesr.p.m.

Warp yarn tension50-55 g.

EXAMPLE 3 By dropping continuously a solution of 0.1 part acrylic amideand 0.009 part of methanol to copolymerized liquid composed of 1 part ofvinyl acetate, 0.155 part methanol, 0.0005 part azobisisobutyronitrile,and 0.0006 acetic acid, polymerization was conducted for about 5 hoursat a temperature of 62-64 C.

A copolymer of vinyl acetate and acrylic amide in the yield of about 70%(was obtained. After separation of the product from vinyl acetatemonomer which has not been polymerized then the said copolymer wasdissolved in methanol to a concentration of 3 parts of said copolymer to7 parts of methanol.

After adding A mole of sodium methylate per one mole of vinyl acetate inthe said copolymer, saponification at a temperature of 30 C. wasconducted. Thus, vinyl acetate and acrylic amide copolymer having asaponification degree 88 mol. percent and polymerization degree 1800 wasobtained. (Item No. 4 of this invention size).

And then by adjusting the above to an aqueous solution composed of thefollowing compositions and then sizing polyester and cotton blend yarnthe property test on the yarns and the weaving test were conducted byuse of a slasher sizing machine.

Then for purposes of comparison like yarns were sized using a mixture of4.5 parts of partially saponified polyvinyl alcohol havingpolymerization degree 1800 and saponification degree 8 mol. percent and0.24 part of Marposol S-80 partially saponified polyacrylic acid ester(manufactured by Matsumoto Fat and Oil Co., Ltd. in the same manner asindicated in the foregoing and the similar sized product was tested.

The results are set forth in Table 2.

TABLE 2.-SIZE YARN PROPERTY AND THE RESULT OF WEAVING TEST Com-Invention parative item size No. 4 No. 3

Acrylic amide content (mol. percent) 1. 1

Size, take up (percent) 10. 7 11. 5

Strength (gm) 186 187 Stretching degree (percent). 10. 1 9.

Friction resistance (times) 2, 219 1, 870 Numbers of sized yarn beingout in (nos./hr.) 0. 2-0 0.

The sizing condition:

Composing of sizing bath- In case of this invention Item No. 4, 4.45%,

comparative size No. 3, 4.78% CMC0.42% Corn starch1.82% Maconol TS-222(manufactured by Matsumoto Fat and Oil Co., Flux)0.42% Kawamoto type 15Dsizer was used in the sizing. Sizing bath temperature80 C. Squeezepressure0.75 'kg./cm. Sizing velocity-25 m./min. Dryingtemperature90-95" C. Weaving conditions:

Used yarn-blend yarn of polyester 65 and cotton 35 45/8 Total number ofwarp yarns-5054 Fabric density-126 x 72/inch Automatic loom rotationtimes185 times/min. Temperature and humidity in weaving operation 6-11C., 55-73% RH Strength: tested by Shimazu Autograph Model P-110 Abrasionresistance: By the time when all 10 sized spun yarns are cut out by useof TM type Friction & Rubbing tester, the times of friction wereexamined. Tension 400 g./10 sized yarns, at a bending angle of 115 wasemployed.

Acrylic amide content 'was calculated from the nitrogen analysis.According to the test result (1), invention item sized yarns aresuperior to those sized by comparative goods in respect of abrasionresistance, the number of warp yarn being cut out in weaving operationwas fewer than those sized by comparative goods, and so it showed higherefficiency in weaving.

EXAMPLE 4 After mixing starch, and flux with an aqueous solution ofinvention Item No. 4 indicated in Example 3 in accordance with thefollowing compositions, and then sizing polyester/cotton blend yam, theweaving test was conducted. h

For comparison purposes, as stated above, after mixing the followingcompound with an aqueous solution composed of 3.47 parts partiallysaponified polyvinyl alcohol (polymerization degree 1800, saponificationdegree 88 mol. percent) 3.47 parts, and 0.35 part of Primal P-6N(manufactured by Nippon Acrylic Co., Ltd. Partially saponifiedcopolymer, comparative goods No. 4), the weaving test was conducted byuse of sized yarn.

The test result showed that with said Invention Item N0. 4 sized yarnswhich have been cut in weaving process slightly numbered below 0.2 yarnper hour, and operation efiiciency was nearly 100%, whereas with thecomparative size No. 4 this figure was 0.6 yarn per hour and theoperation efficiency was The sizing conditions and weaving conditionsare as follows:

Sizing conditions: Percent Invention Item No. 4 or comparative size No.4 3.80 Snow Tex (colloidal silica, manufactured by Nissan Chemical) 0.38Corn starch 4.86 Biscon HHK (Flux, manufactured by Kyoto Gosei) 0.15 MYC(Flux, manufactured by Nippon Fat & Oil Co.) 0.23 Miracon 102 (Flux,manufactured by Daido Kogyo Co.) 0.04

Sizing conditions:

Sizing machine-Suzuki type hot air sizer Temperature of sizing bath94 C.Sizing velocity30-32 m./min. Drying temperature90-95 C. Forafter-waxing, MYC#5000A (manufactured by Nippon Fat & Oil Co.( wasemployed. After-waxing at a temperature of 85 C. was conducted. Kind ofused yarn: Polyester/cotton blend yarn 65/35 34/8 Weaving condition:

Weaving machine-Toyoda Automatic Loom Total warp yarn3874 33/S Fabricdensity85 X 60 yarns/inch Loom rotating times-470 times/min. Temperatureand humidity in weaving-21 C.,

EXAMPLE 5 After preparing aqueous solutions having the followingcompositions set forth below, and then sizing wool yarn by use of saidsizing liquids in a roller sizing machine, the desizing test on thesized yarns was conducted as indicated. One of these size solutions wasmade from Invention Item No. 4, and the comparative one from a mixtureof 5.5 parts of partially saponified polyvinyl alcohol (polymerizationdegree 1800, saponification degree 88 mol. percent), Tamanori Super-40000.5 part vinyl acetate and maleic anhydride copolymer (manufactured byHayashiya firm in Arakawa Ward, Tokyo, (comparative size No. 5). Thesesize solutions had the following compositions.

The composition of the size used was as follows:

Percent Invention Item No. 4 or No. 5 6.0 Corn starch 3.0 Marpolin #1(Flux, manufactured by Watanabe Chemical Co.) 1.0 Bisco HHK (Flux,manufactured by Kyoto Gosei The sizing condition was as follows:

Sizing machine-Kakimoto type two steps Roller Size solutiontemperature60-70" C.

Sizing velocity107 m./min.

Roller rotation times (r.p.m.)No. 1, 4; No. 2, 2.2 Contact angle(mm.)-No. 1, 15; No. 2, 14

7 Thereafter the sized yarns were desized using the fol lowing desizingbath:

Lactogen (manufactured by Rakuto Kasei Co.) 2.0 Bisconol W (manufactureby Nippon Fat & Oil

After the yarns to be desized have been dipped for about 24 hours, inthe said desizing bath at a temperature of 60-80 C. and rinsing withluke warm water and then water washing were conducted.

According to the above test, the yarns sized with invention item No. 4were easily desized by the foregoing method with almost 100%completeness, while in the case of the yarns sized by comparative sizeNo. 5, about 3% of size takeup was observed even after having conducteddesizing. In other words, the desizing process was only partiallyeffective in the latter case.

We claim:

1. A sizing agent for textile yarns and threads consisting essentiallyof a copolymer of acrylic amide and partially saponified vinyl acetate,said copolymer containing from 0.2 to 17 mol percent acrylic amide andfrom 75 to 95% of the acetic acid radicals replaced by hydroxy radicals.

2. A sizing agent according to claim 1 wherein the acrylic amide is 11mol percent, the saponification is 85 mol percent, and thepolymerization degree is 500.

3. A sizing agent according to claim 1 wherein the References CitedUNITED STATES PATENTS 4/1950 Germain 2609l.3 1/1968 Ohara 26029.6

FOREIGN PATENTS 880,980 10/1961 Great Britain.

OTHER REFERENCES Szrnant, H. H., Organic Chemistry, Printice Hall(N.J.), 1957, p. 425.

JOSEPH L. SCHOFER, Primary Examiner C. A. HENDERSON, JR., AssistantExaminer US. Cl. X.R.

